The long-term goal of this project is the development of a multivalent anti-S. aureus vaccine/cocktail of anti-S. aureus mAbs that will be composed of several toxoid antigens or mAbs against the most important S. aureus toxins, respectively. In addition, mAbs against PSM&#945;3 will be an indispensable tool for our planned high-throughput screen for agents inhibiting PSM secretion. Specifically, we plan to: Test all PSM&#945;3 derivatives for their immunogenic potential Test all PSM&#945;3 derivatives (active vaccination) in animal protection assays (using skin, bacteremia, and pneumonia infection models) Produce mAbs against PSM&#945;3 and a selection of PSM&#945;3 derivatives Test the efficacy of those mAbs in protecting from S. aureus-induced disease in various infection models (skin, bacteremia, pneumonia) This project has just started. In the current FY, we have initiated production of polyclonal Abs and mAbs against PSM&#945;3.